73645440 has 192 divisors, whose sum is σ = 258839280. Its totient is φ = 17797120.

The previous prime is 73645427. The next prime is 73645441. The reversal of 73645440 is 4454637.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (192).

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (73645441) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 232162 + ... + 232478.

Almost surely, 2^73645440 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 73645440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (129419640).

73645440 is an abundant number, since it is smaller than the sum of its proper divisors (185193840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

73645440 is a wasteful number, since it uses less digits than its factorization.

73645440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361 (or 338 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 33.

The square root of 73645440 is about 8581.6921408310. The cubic root of 73645440 is about 419.1620481152.

The spelling of 73645440 in words is "seventy-three million, six hundred forty-five thousand, four hundred forty".